Adolf? Not again. My first reaction on learning that not one, but two, substantial new Hitler biographies were up for review was not one of unreserved joy. How much more is there to say? After all, Ian Kershaw’s two volumes from the turn of the century have stood the test of time very well. Nevertheless, as Brendan Simms, a professor in the history of international relations at Peterhouse College, Cambridge, demonstrates in the introduction to his Hitler: A Global Biography, the research grinds on. In his case, he has used a basic cradle-to-ashes format (Simms does not pretend to depict “the ‘whole’ Hitler”) as a frame on which to hang an intriguing — if not always convincing — reexamination of Hitler’s thinking.